Measurement of Excitation and Ionization in an Arc-Heated Supersonic Argon Beam

Abstract

Measured values of fractional excitation and fractional ionization are reported for a 1.52-eV argon beam extracted from an arc-heated supersonic free jet. The data indicate that the ions are molecular during at least a portion of the free-jet expansion, that nearly all of the ions are neutralized during this expansion, and that most of the excited particles formed as a consequence of this neutralization are long-lived.